1. Technical Field
The invention relates to projection technology and, in particular, relates to a micro lens array (MLA) unit used in a liquid crystal display (LCD) projection device, and an LCD projection device.
2. Description of the Related Art
LCD projectors, especially 3LCD projectors, are capable of reproducing bright, natural images that are easy on eyes, and therefore pleasant to watch. These LCD projectors typically employ an LCD panel (three in 3LCD type) for image generation, and the brightness of the reproduced images is mainly determined by the aperture ratio of the LCD panel (the greater the aperture ratio, the higher the brightness). A MLA unit is normally used to increase the brightness. The MLA includes a number of micro lenses, each of which is dedicated to focus incident light into the opening of respective pixels of the LCD panel, thereby increasing the aperture ratio of the LCD panel. However, as the incident light is concentrated by the MLA, peripheral aberrations such as distortion may become greater. In other words, the MLA may decrease the contrast of the reproduced images. It has been challenging to achieve both satisfactory brightness and desirable contrast.
Therefore, it is desirable to provide a MLA unit, and an LCD projection device, which can overcome the above mentioned problems.